Vol. 7, Issue 10 (2018)

Purpose: The purpose of the undertaken study was to synthesize AgNPs from Vitex negundo leaf extract and evaluate their effects on different growth parameters of Cassia occidentalis.

Methods: The AgNPs were synthesized by treating silver nitrate solution with aqueous solution of Vitex nigundo leaves extract. AgNPs were characterized by the analysis of UV-Visible absorptions spectra. The phytotoxic effects of these synthesized AgNPs on seed germination, shoot and root lengths, fresh weight and dry weight of seedlings and leaf surface area of Cassia occidentalis was evaluated in pre-sterilized petri dishes exposed to different concentration of AgNPs.

Results: The AgNPs from Vitex nigundo leaves extract were successfully synthesized and characterized. The results indicated that exposure of AgNPs causes both positive and negative effect on different growth parameters undertaken. AgNPs affected these parameters in concentration dependent manner. The AgNPs at different concentration of 20, 40, and 80 mg/L significantly increased the seed germination, shoot and root lengths, fresh weight and dry weight of seedlings, leaf surface area of C. occidentalis, While AgNPs at 100 mg/L and 1000 mg/L concentration significantly inhibit these parameters. The AgNPs (80 mg/L) was found to be optimal concentration that achieved the highest positive effects on the given parameters.

Conclusion: Finally, AgNPs exhibited both positive and negative effects on different growth parameters in concentration dependent manner. AgNPs can promote plant growth at their optimal concentration without causing any harm to the environment and plants.